Clutch driven hydraulic pump



2 Sheets-Sheet l INVENTOR ATTORNEYS G. D. SHAEFFER Filed May 22, 1943 `CLUTCH DRIVEN HYDRAULIC PUMP Dec. 24, 1946.

G. D. SHAEFFER CLUTCH DRIVEN `HYDRAULIC PUMP Decn 24, 1946.

2 sheets-sheet 2 Filed May 22, 1943 1 N VE N TOR me A TTORNE YS.

- Patented Dec.' 24, 1946 CLUTCH DRIVEN HYDRAULIC PUMP George D. Shaeier, Detroit, Mich., assignmto Gar Wood Industries, Inc., Detroit,'Mlch.

- application Mayi 22, 1943, serial No. 488,023

(c1. a-12e) s claims. l

The present invention relates to road machinery, and particularly relates to a clutch operated pump construction particularly adapted for use on hydraulically operated road machinery.

One of the primary objects of the present invention is to provide improvements in constructions of the type mentioned which are particularly adapted for use on hydraulically operated road machinery and which result in cutting down the operating time of the pump to the times of operation of the scraper work elements in digging, dumping or leveling, or to the times of operation of the work elements of similar ma'- chines. Y

A further object of the invention is to provide improvements in constructions of the type mentioned in which the operating time of the pump is cut down so that the operating temperature of the oil is lower than in prior constructions, thereby increasing the eiciency of the pump and, further, in reducing wear on the pump parts.

A further object of the invention is to provide improvements in constructions of the type mentioned in which a larger capacity of pump can be used on road machinery, thereby making it possible to employ hydraulic actuating means can be used with pumps of a given capacity than have heretofore been practical.

A further object of the invention is to provide improvements in pump and clutch assemblies whereby the clutch elements are accessible for servicing without disturbing the pump elements.

A further object of the invention is to provide improvements in gear pump constructions in which the drive is through one of the pump gears with the clutch at the rear of -the pump, so that it is not necessary to carry the drive around the pump, thereby resulting in a cornpact and economical construction.v

Other objects of the invention will become apparent from the following specification, the drawings relating thereto, and from the claims hereinafter set forth.

In the drawings, in which like numerals are used to designate like parts in the several views throughout:

Figure 1 is a cross-sectional view through a clutch driven gear pump assembly embodying features of the present invention;

Figure 2 is a separated, perspective view of the gear pump employed with the present invention, and

Figure 3 is an end elevational view of a part of the structure shown in Figure 1, illustrating the manner in which the lever is mounted on the housing closure member.

In general, in hydraulically operated road machinery it has been the practice in the past to operate the pump continuously; that is, the pump is operated during the movement of the scraper between the loading andpunloading positons, either when the scraper is loaded or empty, as well as during those periods when the jacks are operated. Operation of the pump during the idle work periods wastefully consumes power. This has resulted in ineiilcient ope'ationbinthat the operating temperature of the oil is quite high, with many resultant disadvantages. The use of pumps on road machinery has 'heretofore been practically limited to pumps having a capacity. g,

of less than seventy-live gallonsper minute, which limit is the result of the high operating temperature of the oil when the pump was continuously operated; and it was found that the bearings seized. With the structurebf the present invention, larger' capacity pumps can be used making it possible to use hydraulic operating means on the larger Scrapers, such as thirty-ve cubic yard Scrapers.

Space and accessibility arev important factors in road machinery construction, and with a structure of the present invention a smaller tank, or reservoir, may be used for a given size pump and the clutch and pump assembly is compact in that the drive passesdirectly through one of the gear pump elements.

Referring to the drawings a pump and clutch assembly is illustrated which comprises a casting I0 formed to provide the main or central pump housing portion. Such casting IIJ is formed with the usual displacement chamber adapted to have rotatably mounted therein pump displacement members l2 and I4 which, in the embodiment illustrated, are intermeshing gear pump elements. The casting I0 is formed with f inlets I6 which communicate with cored passagewaysr I8, such passageways pass around the casting, join at the bottom and communicate with the displacement chamber through the usual inlet (not shown) located at the bottom central portion of the displacement chamber. The displacement members I2 and Il are rctated ,in the 4direction indicated by the arrowsA and fluid, which is introduced through the inlets I6, passes out through an outlet passageway |8a which communicates with the displacement chamber at the upper central portion thereof.

The fluid, such as oil, is supplied from a suitable source, such as the usual tank or reservoir, and the outlet I8 communicates with a conduit leading to a distribution means.

The gear element i2 is freely mounted on a main drive shaft which extends through the casting I0 and projects beyond both sides thereof. The gear I2 is mounted on the shaft 20 and has bearing bushings 22 interposed therebetween so that it may rotate freely with respect thereto.

Wear plates 24 provided with apertures 26 and 28 therethrough are disposed over the sides of the casting I0 in abutting relationship to the ends of the gear elements I2 and |4 to enclose the pump or displacement chamber, so that the oil is displaced around the periphery of the gears from the inlet to the outlet. The wear plates are preferably symmetrical and are provided with pressure relief spaces 30 on opposite sides thereof adjacent the outlet siderof the intermeshing gears, so that such wear plates may be reversed when they become worn on one side. Guide dowels 32 may be formed integral with the casting i0 and are adapted to be received within apertures 34, formed in the wear plates 24, for

vproper positioning and holding the wear plates on the casting I0.

The gear element I4 is mounted on a pump drive shaft 36 and is keyed thereto. The shaft 36 projects through the apertures 28 and extends therebeyond.

An adapter member 40 is fitted over and bears against one of the wear plates 24, and a. housing member 42 is mounted against the other wear plate 24. Suitable bolts may be passed through aligned apertures in the housing, the

casting I0, the wear plates 24 .and the adapter plate for holding the assembly together.

The adapter .member 40 is formed with bearing recesses 44 and 46 therein; and the housing member 42 is formed with an inwardly disposed flange 48 also formed to provide bearing recesses 50 and 52. Ball bearing assemblies 54, including inner and outer races with ball bearings disposed therebetween, are disposed within the bearing recesses 44, 46, 50 and 52 for rotatably mounting shafts 2|] and 36.

One of the projecting ends of the shaft 20 extends within recess 60, formed in the adapter member 40 and is splined as indicated at 62 for connection with a power take-off or other suitable source of power. An end plate 64 is provided which has a central aperturetherethrough through which the splined end of the shaft 20 extends and is fixed to the adapter plate as shown. An oil seal unit 66 is disposed in embracing relationship to the shaft 20 in the space between the plate 64 and assembly 54.

The opposite end of the drive shaft 20 extends within the housing member 42 and has a clutch means operatively connected thereto. Such clutch means is preferably of the cone friction type and includes an annular external clutch member 68 which is fixed to a drive gear 'l0 so that the drive gear 10 and the clutch member 68 rotate together. The clutch member 68 and gear 10 are mounted on shaft 20 for free rotation with respect thereto by means of conventional tapered roller bearing assemblies indicated the adjacent bearing at 12. Such roller bearing assemblies include the usual inner race with rollers disposed between the end of the race and the adjacent surfaces ofthe hub portion of the gear 10. A spacer' collar 14 is mounted around the shaft and between one of the inner bearing races and the adjacent ball bearing assembly 54.v The entire assembly is held in position by means of a lock nut 16 which is received over the threaded portion of the shaft 20 and abuts against the adjacent inner race of the thrust bearing. The clutch element 68 and the gear 'I0 are thus held against axial movement with respect to the shaft 20 but may rotate freely with respect thereto.

The inner end of the shaft 20 is splined as indicated at and adapted to be splined to the inner friction cone member 82. The cone member 82 is thus driven by shaft 20 but may slide longitudinally with respect thereto. When it is moved into engagement with the clutch member 68 it will drive .such clutch member and drive with it gear 10.

In order to drive the pump element I4 a gear 84 is splined to the inwardly projecting end of shaft 36 and is held in place between a spacer collar 86 and a lock nut 88. The gear I4, which is keyed to shaft 36 is thus driven and drives the intermeshing gear pump element I2 so that the fluid pressure is raised and the high pressure fluid passed to the distribution means as mentioned above. The pump is only driven when the clutch elements 68 and 82 are in engagement.'

The means for shifting the clutch element 82 into and out of engagement with clutch member 68 includes a shifter lever 90 which is pivotally mounted on the outer end of a housing closure member 92 through means to be described. Such closure member 92 is fixed to the housing member 42 by means of suitable screws as shown. The member 82 is formed with a cylindrical end portion 94 which is internally threaded as indicated at 96. The shifter is connected to an end cap 98 by means of a U-bolt 99 and the end cap 9B is formed with an annular recess 99a. The U-bolt passes through apertures in the base portion of the lever, which embraces a portion of the cap. 98, and is pulled tightly thereagainst by nuts |03 which are threaded over the ends of the bolt. The cylindrical portion 94 is adapted to be. received within the recess 99a. The inner wall of such recess is formed with threads |0| which are threadably received within the threads 96 so that as the shifter 90 and cap 98rare shifted the cap is caused to rotate and move longitudinally with respect to the housing 82.

The clutch member 82 has an axially extending connector |02 fixed thereto by means cf screws |04. Such connector I 02 is provided with an axial recess |06 into which the end of shaft 20 may extend when the clutch element 82 is moved longitudinally with respect thereto. The opposite end of the connector |02 is reduced and is received within ball bearing assembly |08.

The inner race of such ball bearing assembly embraces the reduced end of the connector with one side of the inner race abutting against a shaft formed on the reduced portion and the other side of the inner race held in place by. means of a lock nut |I0 which is threadably received over the thread end thereof. The outer race of the ball bearing assembly abuts against an annular flange ||2 formed on the inner end of member 98, and a tubular spacer member'I |4 abuts against the other side of the outer race. The assembly is held in place by means of an end plate |I6 which is secured to the outer face of member 98 by means of screws H8.

It will thus be seen that as the lever 90 is rocked the member 98, to which lever 90 is fixed, is correspondingly turned and moves the clutch member 82 axially, thereby shifting it into and out of engagement with its cooperating clutch member 6l. A

An oil seal |20 may be provided between the outer surfaces of cylinder portion 94 and member 98. Oil passageways |22 and |24 are also preferably provided.

What is claimed is:

l. A pump and clutch assembly comprising pump housing means, means providing inlet and discharge ports in said housing means, a main drive shaft disposed within said housing means, a pump drive shaft parallel to said main shaft and disposed in said housing means, intermeshing fluid displacement members disposed within said housing means. one of said members being mounted on said main drive shaft for free rotation with respect thereto, the other of said members being mounted on said pump drive shaft and fixed thereto for rotation therewith, means to connectione end of the main -drive shaft to a power take-off, clutch means connected to the opposite end of said main drive shaft, driving means interconnecting said clutch means and said pump drive` shaft, and manual means to effect engagement and disengagement of said clutch means.

extend bearing against the axial ends of said members and cooperating with said housing means to provide a pump chamber, said shafts extending outwardly beyond said wear plates,`

means to connect one end of the main drive shaft to a power take-ofi', a clutch member fixed to the means interconnecting said second named clutch member and said pump drive shaft, and manual means connected to said first named clutch member to move said first named clutch member into and out of said driving engagement with said second named clutch member.

3. A pump and clutch assembly comprising pump housing means, means providing inlet and 2. A pump and clutch assembly comprising 'l pump housing means, means providing inlet and discharge ports in said housing means, a main drive shaft disposed within said housing means, a pump drive shaft parallel to said main shaft and disposed in said housing means, intermeshing iiuid displacement members disposed within said housing means, one of saidmembers bedischarge ports in said housing means, a main drive shaft disposed within said housingy means, a pump drive shaft parallel to said main shaft and disposed in said housing means, intermeshing gears disposed within said housing means, one of said gears being mounted on said main drive shaft for free rotation with respect thereto, the other of said gears being mounted on said pump drive shaft and fixed thereto for rotation therewith, wear plates having apertures' throughwhich said shafts extend bearing against the axial ends of said gears and cooperating with said housing means to provide a pump chamber, said shafts extending outwardly beyond said wear plates, means to connect one end of the main drive shaft to a power take-oil, a clutch member.

xed to the opposite end of said main drive shaft, another clutch member co-operable with said first named clutch member mounted on said main drive shaft for free rotation with respect thereto, driving means interconnecting said sec' GEORGE D. E" 'l 

